In the construction of wire-bound boxes it is conventional for the bottom, the top, and the walls to be fabricated as separate units and shipped to the customer unassembled. The units can be grouped in convenient quantities of like sizes for the most economical shipment and storage by the customer.
The user of the boxes assembles the units into box form, including threading the loops on the ends of the wires attached to the wall blank and twisting or otherwise fastening the projecting ends of the wires together to tension the wires around the walls to form the rectangular wall structure of the box.
It has been conventional for each wall of the wall structure to comprise a panel or mat, having cleats forming the top and bottom portions of the frame work of the panel. These cleats run the full length of the wall of the box and form the lateral edges of the rectangular wall. The cleats are part of the fundamental framework of the box, when assembled, giving not only strength to the box, but serving to help to maintain the rigidity of the wall of the box against collapse into a parallelogram.
Recently, the scarcity of lumber and high cost of lumber, particularly of good quality and proper length, has made the fabrication of wire-bound boxes much more expensive. In particular, good quality cleats as required in the construction of relatively long boxes, e.g., over six feet long, are not only relatively expensive, but in fact difficult to procure. It is to be understood, of course, that in wire-bound boxes, the width of the cleat is a function of the length. When the cleat is longer, it must also be wider for strength to support the weight of the contents of the box against the bottom of the box, and to avoid distortion of the walls of the box due to horizontal internal pressure by the contents of the box.